Download Ch11 Review Solutions

CHAPTER 11 REVIEW
(Pages 374–375)
Part 1
1. D
2. B
3. B
4. B
5. B
6. B
7. A
8. A
9. 4, 3, 2, 1
Part 2
10. (a)
(b)
(c) In the diagram in part (a), the antigen recognition sites are rounded to match the antigen
on the microbe. These sites are specific only to that microbe. If a person were infected
with the mumps virus, the antibodies produced by the immune system would be specific
to antigens on the mumps virus and would not match the different antigens on the
influenza virus. Therefore, the antibody produced in response to the mumps virus cannot
recognize the antigen of the influenza virus and cannot fight the virus.
(d) From the diagram, one can see that the microbe on its own is quite small. Once the
antibody attaches to it, the combined antigen–antibody complex is much bigger than the
microbe alone, making it easy for the macrophages to find the antigen–antibody complex
and engulf it during phagocytosis.
11. Memory B cells are generated during an infection. These cells contain an imprint of the
invading antigen. The memory B cells identify the reinvading microbe and quickly stimulate
the antibody-producing B cells. The microbe is destroyed before it gains a foothold in the
body.
12. T cells are lymphocytes produced in the bone marrow and processed by the thymus gland;
T cells do not produce antibodies. B cells are lymphocytes processed in the bone marrow that
produce antibodies.
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Unit 20 D Solutions Manual
Copyright © 2008 Thomson Nelson
13. Viruses use the receptor sites on cells as entry ports. The virus injects its hereditary material
into the cell but usually leaves the outer protein coat in the entry port. Different viruses bind
to different sites on different cells. For example, the cold virus has a coat that allows it to
attach to lung cells. HIV attaches to T cells.
14. HIV attaches to T cells. The T cells then engulf HIV. This is a problem because antibodies
need to see the protein coat of the virus to identify and fight it. The virus actually hides in the
cell that is supposed to identify it as an invader and stimulate the antibodies to fight it.
15. Lymphokine is a protein produced by the T cells that acts as a chemical messenger between
other T cells and B cells.
16. (a) Killer T cells puncture the membranes of cells infected with foreign invaders, killing the
cell and the invader.
(b) Helper T cells read a blueprint of the invader and pass it on to B cells, which produce
antibodies.
(c) Suppressor T cells turn off the immune system.
(d) Memory B cells retain information about the shape of an antigen.
17. The indigenous population of Hawaii had never been exposed to measles and the Aboriginal
population of North America had never been exposed to smallpox prior to the arrival of the
Europeans. They had no memory B cells to fight these infections.
18. Pluripotent cells are cells capable of differentiating into a number of different specialized
cells, such as neurons or muscle cells.
19. The number of suppressor T cells, which turn off the body’s immune response, declines with
age, increasing the incidence of rheumatoid arthritis and other autoimmune diseases. This
would suggest that autoimmune diseases increase in frequency with age.
20. A severe food allergy is an anaphylactic reaction that involves the respiratory and circulatory
systems. It is often accompanied by swelling, hives, and itching. When you eat a food you are
allergic to, cells release a chemical messenger called bradykinin that stimulates the release of
another chemical called histamine. Histamine changes the cells of the capillaries, increasing
permeability. Proteins and white blood cells leave the capillary in search of the foreign
invader, but in doing so, they alter the osmotic pressure. The proteins in extracellular fluid
create another osmotic force that opposes the osmotic force in the capillaries. Less water is
absorbed into the capillaries, and tissues swell. Weakness, sweating, and difficulty breathing
can occur. Nausea, diarrhea, and a drop in blood pressure may also occur.
21. Patient X likely has lead poisoning because both the red blood cell and the white blood cell
counts are lower than normal. Lead destroys the bone marrow, which is where both types of
blood cells are produced.
22. Patient Z likely has a viral infection because the white blood cell count is higher than normal
and the body temperature indicates a fever, both of which indicate that the body is fighting an
infection.
23. Patient Y likely has leukemia because the white blood cell count is higher than normal, which
occurs in leukemia.
24. The search for a treatment might include finding an antibiotic to kill the bacterium.
Physicians might look for the presence of the associated bacteria as a way of predicting
problems or diagnosing disease.
25. Antibodies indicate the presence of the microbe linked to the disease.
Copyright © 2008 Thomson Nelson
Unit 20 D Solutions Manual
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